Gun barrel



Patented July 5, 1927.

narran stares .ears-.ar "oe-eren.

NICOLAS EMILIEN METHLIN, OFY PARIS, FRANCE, ASSIGNOR TO SCHNEIDER &GIE.,` 0F PARIS, FRANCE, A. LIMITED JOINT-STOCK COMPANY.

GUN BARREL.

Application inea october 25, 1926, serial No. 144,067, and ijn FranceJanuary 14, 192e.

. The present invention relates to agun b arv` rel adapted to be takendown or dismounted, comprising a acket forming a breech sleeve at itsback part and a tiring. tube encased at its back part in the saidjacket.

According to the invention the thickness of the tiring tube, itsexternal diameter and the nature or state of the metal of which it iscomposed are chosen in such a way that when the gun barrel is mounted aclearance is left between. the back part of the tube and the interioroiv the jacket which is taken up each time a shot is fired inV orderthat the jacket will assist the gun barrel in withstanding thetransverse stresses set up, the

said clearance re-appearing automatically,

however, after the projectile has lett the gun, thus enabling a worntiring tube to be easily removed and replaced by a new tube.

In order that the jacket will take part in withstanding the transversestresses set up in the gun barrel during firing, that is to say, inorder that the assembling clearance will disappear momentarily whilere-appearing automatically subsequently when the deforming. force due tothe pressure of the gases has ceased to act,a metal having a higherelastic limit than the meta-l of the jacket. may be chosen for thetiring tube.

The jacket and the firing tube may also beV both. made of the same steeland the steel of the tiring. tube have a higher elastic limit impartedto it by a suitable treatment.

The. removable tiring tube may also be made of a metal having,.indesired cases, an elastic. limit lower than that of the metal formingthe jacket. In this case it will be necessary to.- subject the tube, ina preliminary operation, before the machining of the tube, to altreatment which. raises the elastic limit of thev outer layers of thetube, mak.

ing it higher than the elastic limit of the inner layers of the jacket.This eiiect may be obtained by subjecting the tiring tube, beforemachining, to a. self hooping. operation.

Several embodiments oi the present inven* tion are disclosed in theaccompanying drawings wherein like reference characters refer tolikeparts throughout the several views. It will be understood, however,that the drawings are for purposes of illustration only and are notdesigned as a definition of the limits of the invention, reference beinghad to the appended claims .for this purpose.

` In the drawings, Figs. 1 'and la constitute a longitudinal sectionalview of one embodiment ot the invention. Figs.` 2,. 2 and 3 are similarviews illustratinn other embodiments..

In the exampleshown in longitudinal section-al elevation in Figure 1 theytiring tube A inserted from the front in the jacketrB with a clearanceD is screwthreaded lata for itsassembly with the jacket which isprovided with aYV corresponding female thread This thread is ot' theopposite hand to the riding ofthe tube. Y A

The rear end ot' thetube lis turned down ,at al to form` a shoulder a2Vby meansA of which the tube" presses upon an abutment b1 formed uponvthe jacket. Y

As the screwed joint .and the riiing have opposite handed threads nounscrewing of the tube can take pla-ce during firing; moreover, the tubeis always made to abut against the. shouldergin the jacket by thescrewing action, which the reaction due to the rotationot` theprojectile in the tube tends to produce in the desireddirection.

In the modiiication shown in longitudinal sectional elevation in Figure2. a shoulder is formed at a3 by a thickening of the firing tube A,which shoulderv abutsY against the front tace b2 of the jacket B. Inthis eX- ample the turned down portion is dispensed with in the backpart of the tube, thusV al- ,lowing a tube of less thickness to be em-Vmeans of a sleeve .E having an internal thread and adapted to screw onto a screw# threadI end B? of the jacket. In this eX- ample theiront/face of the jacket abuts against a collar A1 on the tiring tube,which collar in its turn abuts against a shoulder e Having nowparticularly described and ascertained the nature ot my said inventionand in what manner the same is to heupenV formed, I deelarethat what Iclaim is l. A gun comprising a ritledl ring tube and a jacket, the rearend of said tube eX- tending into said jacket and having theV outerdiameter ot the rear portion thereof less than the inner diameter of thejacket, and 4 screwthreaded means forY removably securing said iiringtube to said jacket, the threads ot said means being formed inv adirection opposite to the ritiing of the tube and being provided.adjacent the front end ot the jacket whereby said firing tub-e isreadily removable from the acketV which assists in withstanding thetransverse stresses set up in the rear portion of said tube duringtiring ot the gun.

2. A gun comprising a rifled tiring tube and a jacket provided withscrew threads adjacent thev torwardend thereof, the rear end ot saidtube extending into said jacket and being provided with'means to engagesaid threads, the latter being formed in a `direction opposite to theritling of the tube, the outer diameter ot the rear portion ot the tubebeing less than the inner diameter of the jacket which is adapted Ytoconfine the rear end ot the tube within its elastic limits under stressof lire while leaving play'between the tube and jacket when relieved otsuch stress, whereby said'tube is'readily removable trom said jacket. Y

3. A gun comprising a riiledY iiring vtube and a jacket having athreaded portion, the rear end or" said tube extending into thejacketand having an outer diameter nor mally less than the vinnerdiameter ot the jacket, and threaded means for the tube adapted toengage the threads ot the jacket for maintaining said jacket and tuberincooperative relation, said threads being formed in a direction oppositeto the riiling ot the tube.

' 4. A gun comprising a rifled tiring tube and a'jacket having threadsadjacent the forward end thereof, the rear end ot said tube extendinginto the jacket and provided with threads formed in an oppositedirection to the ritling of the tube for coaction with the threads ofthe jacket, the outer diameter of the rear portion of the tube beingless than `the inner diameter ot the jacket and having a tensilestrength ,such that the jacket assists in withstanding the transversestresses set up in the tube at the instant ot iring, said tube beingprovided with a shoulder adapted to abutv against a portion of thejacket, the reaction resulting from the rotation otV a projectilepassing through the tube serving to torce said shoulder more tightlyinto engagement with the jacket. i 5. A gun ot the type comprising innerand outer portions', 'the inner diameter ot the outer portion andthe'outer diameter of the inner portion being such that the outerportion coniines the inner portion within its elastic limit under tiringstresses while leaving play between'saidinner and outer portions vwhenrelieved ot ssaid stresses, said in ner and outer portions beingprovided with coacting threads and the inner portion being rifled, theritling and threads beingso formed that the reaction resulting from thepassage ot a projectile through theinner portion tends to move thelatter inwardly relative to the outer portion. j 6. A gun comprising aninner rifled portion and an outer portion, a shoulder on one ot saidportions having abutting engagey ment with the other portion, threadedmeans .for securing said portions 1n cooperative relation, the threadsot said means being cut ina direction oppositeto the rifling whereby thereaction resulting from the rotation of a projectile passing through theinner portion acts through said threads and forces said shoulder moreclosely into `engagement with the abutting portion.

7 A gun comprising, incombination, a jacket and a ritled tiring tubehaving the rear portion thereof extending within the bore of the jacket,said tube being provided with Vmeans adapted to engage threads formed inthe forward portion ot said jacket, saidV threads being formed in adirection opposite to the riiiing ot said ring tube, the outer diameterot the rear portion ot the part ot the tube extending rearwardly fromthe plane ot the threads ot the jacket being lessvthan theinner diameterof the jacket, and .said diameters being so proportioned that thejacket'conlines said tube within `its elastic limits und-er the stressof firing while leaving play between the tube and jacket when relievedot ysuch stress, whereby said tube is rendered easily removable.

8. A gun ot thetype described compris ing, in combination, a jacket andaried iiring tube extending into -said jacket, said tube being providedwith a shoulder adapted to engage the end of said jacket, and the latterbeing provided with a sleeve surroundving said tube and adapted toengage said shoulder and the threads ot said jacket ttor preventinglongitudinal displacement of the tube and jacket.

9. VA Agun comprising, in combination, a jacket, a rifled firing tubeextending into said jacket and provided with a shoulder adapted toengage the jacket, screw threads formed in the jacket adjacent theforward 130 end thereof for coacting with said tube to maintain thelatter in operative relation with the jacket, said screw threads beingformed in a direction opposite to the rifling of the tube, and the innerportion of said tube being confined within said acket within its elasticlimits under the stress of liring and being so constructed that play isleft between the tube and jacket when the former is relieved of saidstress, whereby 10 said tube is rendered easily removable.

In testimony whereof I have Signed this specification.

NICOLAS EMILIEN METHLIN.

